Projectile guidance system

ABSTRACT

A guidance system for deployment on-board a projectile includes a laser-seeking detector, an imaging device, and a control module. The laser-seeking detector is designed to detect the position of the projectile with reference to a laser spot on a target. The imaging device is designed to capture one or more images in front of the projectile. The control module is designed to control a flight direction of the projectile based on input received from the laser-seeking detector in a first mode, control the flight direction of the projectile based on input received from the imaging device in a second mode, and switch between the first mode and the second mode while the projectile is in flight towards the target. Both guidance technologies are leveraged to develop an improved guidance technique that provides highly accurate targeting and allows for a faster rate of fire to deal with multiple targets.

BACKGROUND

Precision guidance systems for projectiles, such as precision guided munitions, are used in various applications, including targeting applications. By efficiently and effectively determining correct targets from incorrect targets, the risk of collateral or otherwise unintended damage is minimalized. Precisely guiding a projectile to a correct target that is closely grouped with other structures or vehicles, such as in the case of a swarm attack, is difficult due to the proximity of so many similar-looking targets.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of embodiments of the claimed subject matter will become apparent as the following Detailed Description proceeds, and upon reference to the Drawings, in which:

FIG. 1 illustrates a vehicle engaging with a plurality of targets, in accordance with some embodiments of the present disclosure.

FIG. 2 illustrates an example of targets in close proximity with non-targets, in accordance with an embodiment of the present disclosure.

FIG. 3 illustrates a projectile, in accordance with an embodiment of the present disclosure.

FIG. 4 illustrates a guidance system of a projectile, in accordance with an embodiment of the present disclosure.

FIGS. 5A-5D illustrate various stages of a vehicle engaging with a plurality of targets, in accordance with some embodiments of the present disclosure.

FIGS. 6A and 6B illustrate different outputs of a guidance system of a projectile, in accordance with some embodiments of the present disclosure.

FIGS. 7A and 7B illustrate data plots of target engagement distances, in accordance with some embodiments of the present disclosure.

FIG. 8 illustrates a flowchart of a method of guiding a projectile, in accordance with an embodiment of the present disclosure.

FIG. 9 illustrates a flowchart of a method of launching one or more projectiles to engage with multiple targets, in accordance with an embodiment of the present disclosure.

Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent in light of this disclosure.

DETAILED DESCRIPTION

Techniques are disclosed for guiding projectiles to a designated target or targets. The techniques are particularly useful in defending against a swarm attack that consists of multiple attacking vehicles in close proximity to one another.

One way to guide a projectile to a specific target is to use a laser targeting system where a laser is “locked on” to the designated target and the projectile tracks the laser and guides itself to the laser spot, thus destroying the marked target. However, this system suffers from some issues. First, the system requires that the laser spot be maintained on the target throughout the flight duration of the projectile. This can be difficult to achieve for fast-moving targets and is also difficult to maintain in marine applications where small boats can be obscured by rising and falling waves. Second, the need to maintain the laser on a single target until that target is destroyed yields a slow firing rate, which may not be viable in the swarm attack scenario where multiple targets need to be engaged quickly. Other guidance techniques have used image processing systems to capture images (e.g., video) in front of the rocket and use complex algorithms to differentiate between possible targets to choose the desired target. The projectile is then guided towards the chosen target. Although such guidance systems allow the operator to essentially “fire and forget” the projectile before moving on to another task, these image guidance techniques are more prone to false target identification.

According to an embodiment of the present disclosure, both laser-based and image-based guidance technologies are leveraged to develop an improved guidance technique that provides highly accurate targeting and allows for a faster rate of fire to deal with multiple targets. In an embodiment, a guidance system for deployment on-board a projectile includes a laser-seeking detector, an imaging device, and a control module. The laser-seeking detector is designed to detect the position of the projectile with reference to a laser spot on a target. The imaging device is designed to capture one or more images in front of the projectile. The control module is designed to control a flight direction of the projectile based on input received from the laser-seeking detector in a first mode, control the flight direction of the projectile based on input received from the imaging device in a second mode, and switch between the first mode and the second mode while the projectile is in flight towards the target. The switching between modes may occur in a dynamic fashion, and in some such example embodiments is based on the distance between the projectile and the intended target.

General Overview

FIG. 1 illustrates a potential engagement scenario between a friendly vehicle 102 and a swarm of enemy vehicles 104. Friendly vehicle 102 may be an airborne vehicle such as a helicopter, drone, or fighter jet to name a few examples. Enemy vehicles 104 may be boats, tanks, or all-terrain vehicles to name a few examples. In the following discussion, for simplicity, friendly vehicle 102 is a helicopter while enemy vehicles 104 are boats, although other scenarios are contemplated including land assets such as combat vehicles.

Friendly vehicle 102 can include a laser source 106, such as a red diode laser. When the pilot is ready to engage with enemy vehicles 104, laser source 106 may be activated to form a targeting beam 108 trained on a particular enemy boat 110 of the swarm of enemy vehicles 104. A projectile 112 is launched from friendly vehicle 102 towards enemy vehicles 104. In some other examples, projectile 112 is launched from a different location than friendly vehicle 102. Likewise, the laser source can be independent and at a different location from the friendly vehicle. Projectile 112 can be any guided munition including a motorized device that carries a warhead payload, such as a rocket.

Projectile 112 includes sensors to track the location of targeting beam 108 on the particular enemy vessel or boat 110. The location of targeting beam 108 is used to guide projectile 112 along a trajectory 114 to intercept enemy boat 110. If targeting beam 108 is lost, or if targeting beam 108 loses its mark on enemy boat 110 for any other reason, projectile 112 may lose the ability to track enemy boat 110 and may miss the target. As can be appreciated from this example, friendly vehicle 102 typically must wait until projectile 112 has hit its target before it can train targeting beam 108 onto a different boat of the swarm of enemy vehicles 104 and launch another projectile. This time between attacks can prove costly in situations where every second counts.

FIG. 2 illustrates another example of a swarm of vehicles 202 that includes both enemy vehicles 204 and friendly vehicles 206. For example, friendly vehicles 206 can be civilian boats in close proximity (e.g., less than 100 meters) to other enemy vehicles 204 in the swarm of vehicles 202. Although laser-guided targeting techniques could still be used to pinpoint a particular enemy boat from the swarm of vehicles 202, other image-based guiding techniques can struggle to differentiate enemy vehicles 204 from friendly vehicles 206. Compounding this problem is that friendly vehicles 206 may look very similar (same basic size, heat signature, etc.) to enemy vehicles 204 even at relatively short distances away. In some situations, by the time the projectile is able to determine that the target it was tracking is not an enemy vehicle, it may be too late to change the course of the projectile.

Embodiments herein describe a new projectile guidance technique that can correctly differentiate between friendly vehicles and enemy vehicles without requiring continuous laser tracking of the target. According to an embodiment, the new projectile guidance system uses laser tracking to initially “mark” a particular target and then hands off the tracking to an image-based system while the projectile is in flight. The image-based system then guides the projectile towards the object that had been previously marked with the laser. The image-based system does not need to perform complex image processing algorithms to determine friendly targets from enemy targets. Rather, according to an embodiment, the image-based system tracks whatever object is illuminated with the laser, and then continues to track that object after the laser spot has been removed. The hand-off between the laser-based guidance system and the image-based guidance system on the projectile may occur when the projectile is a given threshold distance away from the target. In another example, the hand-off between the laser-based guidance system and the image-based guidance system is based on a determination that a target observed from the image-based guidance system is in the same angular location as indicated by the laser-based guidance system.

The new projectile guidance technique discussed herein has many advantages over previous guidance systems. First, there is no need to power up the guidance system on the projectile and download data to the projectile before it is launched. Rather, the projectile can be launched immediately and can fixate on the laser spot while in-flight, and then hand-off to the image-based guidance system without receiving any other information from outside sources. Second, no modifications are needed to the launching platform to facilitate prelaunch powerup and data transfer to the projectile. Third, the ability to hand-off the guidance to the image-based guidance system while the projectile is in flight, provides valuable additional time for the pilot to either target another enemy and launch another projectile, or to take evasive action or flee while the projectile remains on course to intercept its target.

Projectile Guidance System

FIG. 3 illustrates a projectile 300 having a projectile guidance system 302, according to an embodiment. Projectile 300 may be a rocket, such as any type of air-to-ground or air-to-air rocket. Projectile 300 includes a guidance system 302 having an imaging detector 304 and a guidance component 306. In some embodiments, projectile 300 also includes a warhead 308 and a motor section 310. In some other embodiments, projectile 300 does not include motor section 310. For example, motor section 310 may not be employed for projectiles that are dropped or launched and lack independent propulsion. The shapes and sizes of the various components of projectile 300 are used for illustrative purposes only and not to be considered limiting. Furthermore, the order of the components along a length of projectile 300 may vary.

According to an embodiment, guidance system 302 includes a laser detector for performing laser-based guidance of projectile 300. The guidance system 302 in one example can be enhanced by employing global positioning system (GPS) data to the extent it is available. In certain GPS-denied environments the GPS data may be wholly or partially lacking. The laser detector may be a part of either imaging detector 304 or guidance component 306. In one example, guidance system 302 uses input from one or both of imaging detector 304 and the laser detector to guide projectile towards the intended target. The guidance may be performed by a guidance controller within guidance component 306 that controls mechanical flaps and other mechanical components on wings of projectile 300 to affect the azimuth angle and elevation angle as projectile 300 travels towards the target. Further details on the components of guidance system 302 are provide with reference to FIG. 4.

Warhead 308 can include any type of explosive material. In some embodiments, warhead 308 includes conventional chemicals such as gunpower or high explosive materials. In some embodiments, warhead 308 includes metal fragments or metal bars that are projected at very high velocity by a blast to cause damage or injury. Warhead 308 may be located at any point along a length of projectile 300.

According to one embodiment, motor section 310 includes a combustion engine of any known type to burn fuel and propel projectile 300 forward. The fuel may be stored in motor section 310 or may have a separate compartment in another section of projectile 300. The fuel may be either liquid fuel or solid fuel.

FIG. 4 illustrates a more detailed schematic of guidance system 302 to be used on projectile 300, according to an embodiment. Guidance system 302 includes a processor 402, an imaging camera 404, a laser detector 406, a guidance controller 408, and a transceiver 410. In some embodiments, the operations performed by guidance controller 408 are performed by processor 402 instead, and a separate guidance controller is not required. Additionally, in various embodiments, guidance system 302 may not include one or more of the components illustrated in FIG. 4, but guidance system 302 may include interface circuitry for coupling to the one or more components. For example, guidance system 302 may not include imaging camera 404, but may include interface circuitry (e.g., a connector and driver circuitry) to which imaging camera 404 may be coupled.

Processor 402 may be designed to control the operations of the various other components of guidance system 302. Processor 402 can represent one or more processors. As used herein, the term “processor” may refer to any device or portion of a device that processes electronic data from registers and/or memory to transform that electronic data into other electronic data that may be stored in registers and/or memory. Processor 402 may include one or more digital signal processors (DSPs), application-specific integrated circuits (ASICs), central processing units (CPUs), graphics processing units (GPUs), cryptoprocessors (specialized processors that execute cryptographic algorithms within hardware), server processors, or any other suitable processing devices. Guidance system 302 may include memory, which may itself include one or more memory devices such as volatile memory (e.g., dynamic random access memory (DRAM)), nonvolatile memory (e.g., read-only memory (ROM)), flash memory, solid state memory, and/or a hard drive. In some embodiments, the memory may be integrated on a same die with processor 402.

Imaging camera 404 is designed to capture images around the projectile, according to an embodiment. Imaging camera 404 may capture images primarily from the front of projectile 300. The images may be captured at any speed and can include video capture at any framerate. In some embodiments, imaging camera 404 is an infrared camera and captures thermal images. The thermal images may be used by processor 402 to identify and distinguish vehicles in the images. Imaging camera 404 may operate at wavelengths as long as 15 μm.

Imaging camera 404 may include any number of photodiodes or charge coupled devices (CCDs) to receive electromagnetic radiation in a given wavelength range. In the case of an infrared camera, the wavelength range can be from around 700 nm to around 15 μm. The received radiation can be analyzed by processor 402 to determine the location of particular objects with respect to projectile 300.

Laser detector 406 may represent one or more optical detectors located at different portions of projectile 300. In some examples, an optical detector is located at each wing of projectile 300. Laser detector 406 includes the necessary optical components to track and determine with a high degree of accuracy the location of a laser spot on an intended target. In some embodiments, laser detector 406 is capable of tracking the location of a laser spot that is up to 5 km away.

Guidance controller 408 may represent one or more processing devices designed to control the flight path of projectile 300. In some embodiments, guidance controller 408 receives input from processor 402 regarding the location of an intended target. In some embodiments, guidance controller 408 receives input from an inertial navigation system (INS) located on projectile 300. In some embodiments, guidance controller 408 obtains GPS data for some portion of the flight that can be used to identify position and tracking. According to some embodiments, guidance controller 408 uses the input from the INS and the determined location of the intended target from processor 402 to affect an azimuth angle and/or an elevation angle of projectile 300 to ensure that projectile 300 remains on course to intercept the intended target. As noted above, one or more of the operations of guidance controller 408 may also be carried out by processor 402.

According to some embodiments, guidance controller 408 may operate in a first mode where the guidance of projectile 300 is based on input received only from laser detector 406, or in a second mode where the guidance of projectile 300 is based on input received only from imaging camera 404. Directly after launch of projectile 300, guidance controller 408 may operate in a first mode until a later point in time during the flight of projectile 300 when guidance controller 408 switches over to operate in the second mode. In some examples, guidance controller 408 switches from the first mode to the second mode when projectile 300 is a given distance from the intended target. The given distance may be between about 1.5 km and about 2.5 km. In one particular example, the given distance is about 2 km. According to some embodiments, if projectile 300 is launched within the threshold distance to the intended target, then guidance controller 408 only needs to operate in the first mode long enough for processor 402 to determine the location of the laser spot, and then can switch over to operate in the second mode. For example, if projectile 300 is launched within the threshold distance to the intended target, processor 402 may only need about 500 ms to identify the laser-marked target, after which time guidance controller 408 can switch over to operate in the second mode. In another example, guidance controller 408 switches from the first mode to the second mode when it determines that a target observed in the images from imaging camera 404 is in the same angular location as indicated by laser detector 406.

In some embodiments, during the first mode of operation of guidance controller 408, imaging camera 404 continues to capture images and track the location of the laser-marked object. In this way, when guidance controller 408 switches over to operate in the second mode, imaging camera 404 is already trained on the object with the laser spot and can continue to track the object even after the laser spot has been removed.

Transceiver 410 may be designed to manage any wireless communication either received at projectile 300 or transmitted from projectile 300. The term “wireless” and its derivatives may be used to describe circuits, devices, systems, methods, techniques, communications channels, etc., that may communicate data through the use of modulated electromagnetic radiation through a nonsolid medium. Transceiver 410 may implement any of a number of wireless standards or protocols, including but not limited to Institute for Electrical and Electronic Engineers (IEEE) standards including IEEE 802.16 standards (e.g., IEEE 802.16-2005 Amendment), LTE project along with any amendments, updates, and/or revisions (e.g., advanced LTE project, ultra mobile broadband (UMB) project (also referred to as “3GPP2”), etc.). Transceiver 410 may operate in accordance with a Global System for Mobile Communication (GSM), General Packet Radio Service (GPRS), Universal Mobile Telecommunications System (UMTS), High Speed Packet Access (HSPA), Evolved HSPA (E-HSPA), or LTE network. Transceiver 410 may operate in accordance with Enhanced Data for GSM Evolution (EDGE), GSM EDGE Radio Access Network (GERAN), Universal Terrestrial Radio Access Network (UTRAN), or Evolved UTRAN (E-UTRAN). Transceiver 410 may operate in accordance with Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Digital Enhanced Cordless Telecommunications (DECT), Evolution-Data Optimized (EV-DO), and derivatives thereof, as well as any other wireless protocols that are designated as 3G, 4G, 5G, and beyond. Transceiver 410 may include one or more antennas to facilitate wireless communications.

According to some embodiments, transceiver 410 may transmit a signal indicating that the guidance system has switched from the first mode to the second mode (e.g., guidance no longer requires the laser spot to track the target.) The signal may be sent back to whichever vehicle launched projectile 300, or to any other operator within range. The signal may be used to alert an operator that laser tracking is no longer needed for this projectile, thus allowing the laser to be aimed elsewhere, or for any other actions to be taken.

Examples of Operation

FIGS. 5A-5D illustrate an example encounter between friendly vehicle 102 and a swarm of vehicles 502 that include both enemy vehicles (solid rectangles) and friendly vehicles (unfilled rectangles), while using the improved projectile guidance system to engage with the enemy vehicles, according to some embodiments. During an initial stage of the encounter illustrated in FIG. 5A, friendly vehicle 102 may be around 5 km away from swarm of vehicles 502 when a first projectile 504-1 is launched towards a first enemy target 506. A laser beam 508 is aimed from friendly vehicle 102 such that the laser spot is on first enemy target 506. In some embodiments, laser beam 508 originates from a location other than friendly vehicle 102. In some embodiments, first projectile 504-1 is launched from a location other than friendly vehicle 102. First projectile 504-1 may be similar to projectile 300 having the advanced guidance system according to some embodiments discussed herein. Laser beam 508 may be aimed at first enemy target 506 before launching first projectile 504-1, or shortly after launching first projectile 504-1.

After launch, the guidance system onboard first projectile 504-1 tracks the laser spot and guides first projectile 504-1 along a trajectory 510 to intercept first enemy target 506. While operating in a first mode, the guidance system only guides first projectile 504-1 based on input from the laser detector, but an imaging camera onboard first projectile 504-1 is also tracking the position of first enemy target 506 by tracking the object in its captured images that includes the laser spot.

FIG. 5B illustrates the engagement scenario sometime after the situation illustrated in FIG. 5A. Here, first projectile 504-1 has reached a threshold distance d from first enemy target 506. The threshold distance may vary depending on the situation and can be pre-programmed into first projectile 504-1. The threshold distance in one example is around 2 km.

Upon reaching the threshold distanced, the guidance system onboard first projectile 504-1 switches from a first mode (laser-based guidance) to a second mode (image-based guidance). The captured images from the imaging camera are used to track the location of first enemy target 506 in the second mode.

Upon switching to the second mode, first projectile 504-1 transmits a signal back to friendly vehicle 102 indicating that laser-based targeting is no longer required for first enemy target 506, according to some embodiments. Upon receipt of the signal, an operator of friendly vehicle 102 may manually remove laser beam 508 from targeting first enemy target 506. In another example, upon receipt of the signal, friendly vehicle 102 may automatically remove laser beam 508 from targeting first enemy target 506. In some other embodiments, friendly vehicle 102 tracks, or estimates based on certain known variables, the position of first projectile 504-1 and its distance from first enemy target 506. In this way, friendly vehicle 102 can detect when first projectile 504-1 reaches the threshold distance d from enemy target 506 and can alert the operator to remove laser beam 508 from targeting first enemy target 506 or can automatically remove laser beam 508 from targeting first enemy target 506.

FIG. 5C illustrates the engagement scenario sometime after the situation illustrated in FIG. 5B. Here, first projectile 504-1 is being guided towards first enemy target 506 using image guidance without the aid of a laser spot. This allows laser beam 508 to be directed towards a second enemy target 512 and a second projectile 504-2 to be launched along a second trajectory 509 towards second enemy target 512. Second projectile 504-2 may be similar to projectile 300 having the advanced guidance system according to some embodiments discussed herein. Laser beam 508 may be aimed at second enemy target 512 before launching second projectile 504-2, or shortly after launching second projectile 504-2.

Second projectile 504-2 is launched and guided towards another enemy target before first projectile 504-1 has reached its enemy target, according to an embodiment. Any number of projectiles may be launched in this way and any number of projectiles may be simultaneously inflight towards their intended targets.

FIG. 5D illustrates the engagement scenario sometime after the situation illustrated in FIG. 5C. First projectile 504-1 has impacted first enemy target 506 while second projectile 504-2 continues along its trajectory towards second enemy target 512. Depending on the range between friendly vehicle 102 and swarm of vehicles 502, and the flight speed of the projectiles, second projectile 504-2 may already have reached its threshold distance by the time first projectile 504-1 strikes first enemy target 506.

FIGS. 6A and 6B illustrate example outputs from the laser guidance system (FIG. 6A) and the imaging camera (FIG. 6B) onboard a projectile at or near the moment that the guidance system switches from laser-based guidance to image-based guidance, according to some embodiments. As shown in FIG. 6A, a laser spot 602 is tracked to determine an azimuth angle and elevation angle to laser spot 602. The projectile is guided towards laser spot 602 in the first mode of operation (i.e., laser-based guidance).

FIG. 6B illustrates an example image output from the imaging camera at or near the moment that the projectile switches to the second mode of guidance operation (i.e., imaged-based guidance). The example image includes an enemy target 604 and non-target objects 606. Enemy target 604 is positioned at substantially the same azimuth and elevation angle of laser spot 602. Accordingly, since the guidance system was tracking laser spot 602, it can now lock on to enemy target 604 from the received images as enemy target 604 will be the only object at the same location previously occupied by laser spot 602. Thus, even after laser spot 602 is removed, the guidance system can continue to track enemy target 604 for the remainder of the projectile's trajectory, according to an embodiment. Furthermore, enemy target 604 can be successfully distinguished even when non-target objects 606 look substantially similar (such as all being small boats), due to the initial laser-based guidance to enemy target 604 using laser spot 602.

FIGS. 7A and 7B illustrate simulated results of distances to engagement of multiple enemies spaced apart in the Y-direction and moving at the same speed in the X-direction. FIG. 7A represents a simulation using only laser-based guidance of the projectiles to the enemy targets. FIG. 7B represents a simulation using the improved guidance system according to some of the embodiments discussed herein. It will be appreciated that these simulations represent one particular engagement scenario for the sake of comparison, and that other scenarios will vary depending on numerous factors.

As shown in FIG. 7A, eight projectiles are launched to intercept 8 targets as they move in the X-direction. The eight projectiles are launched one after the other from a friendly vehicle as it moves along a trajectory 702. Since the friendly vehicle must wait until a projectile hits its target before firing the next projectile, only eight targets have been destroyed before the friendly vehicle moves too close (e.g., is within the enemy's firing range).

In contrast, FIG. 7B illustrates how 15 projectiles are launched to intercept 15 targets as they move in the X-direction. The eight projectiles are launched one after the other from a friendly vehicle using the advanced guidance system discussed herein as the vehicle moves along a trajectory 704. Since the friendly vehicle does not need to wait for a projectile to hit its target before filing the next projectile, the firing rate is increased, and more targets can be destroyed before the friendly vehicle moves too close (e.g., is within the enemy's firing range).

Methodology

FIG. 8 is a flowchart illustrating an example method 800 for guiding a projectile to a target, in accordance with certain embodiments of the present disclosure. As can be seen, the example method includes a number of phases and sub-processes, the sequence of which may vary from one embodiment to another. However, when considered in the aggregate, these phases and sub-processes form a process for guiding a projectile in accordance with certain of the embodiments disclosed herein. These embodiments can be implemented, for example using the guidance system illustrated in FIG. 4 as described above. However other system architectures can be used in other embodiments, as will be apparent in light of this disclosure. To this end, the correlation of the various functions shown in FIG. 8 to the specific components illustrated in the other figures is not intended to imply any structural and/or use limitations. Rather, other embodiments may include, for example, varying degrees of integration wherein multiple functionalities are effectively performed by one system. For example, in an alternative embodiment a single module having decoupled sub-modules can be used to perform all of the functions of method 800. Thus, other embodiments may have fewer or more modules and/or sub-modules depending on the granularity of implementation. In still other embodiments, the methodology depicted can be implemented as a computer program product including one or more non-transitory machine readable mediums that when executed by one or more processors cause the methodology to be carried out. Numerous variations and alternative configurations will be apparent in light of this disclosure.

Method 800 may begin at operation 802 where a laser detection system on the projectile receives a location of a laser spot from a marked target. The laser detection system may include a plurality of detectors located around the projectile to accurately determine the location of the laser spot.

Method 800 continues with operation 804 where the projectile is guided to the laser-marked target. According to an embodiment, the projectile is guided using a guidance system that steers the projectile in midflight to bring the projectile to the laser-marked target. Steering the projectile may involve affecting one or more of an azimuth angle and an elevation angle of the projectile.

Method 800 continues with a decision block 806 where a determination is made regarding the distance between the projectile and the target. If the target is within a threshold distance away from the projectile, then method 800 proceeds with operation 808. If the target is not yet within the threshold distance away from the projectile, then method 800 loops back to operation 804 and continues to guide the projectile towards the laser-marked target. The threshold distance may be about 2 km, although this distance may change depending on various factors, such as the type and speed of the enemy target or the velocity of the projectile, to name a few examples. The guidance system on the projectile may calculate the current range between the projectile and the marked target using a variety of known parameters, such as the current velocity of the projectile, a launch position of the projectile, and an initial position of the marked target. The calculated range between the projectile and the marked target may be an estimate, since determining the exact range is not necessary for performing the handoff between guidance techniques.

If “yes” is determined from decision block 806, then method 800 proceeds to operation 808 where the projectile is guided to the target using captured images from an imaging camera. The captured images may be from a camera taking images from the front of the projectile. The images may be infrared images taken from an infrared camera. Unlike some conventional imaging guidance techniques, complex image recognition analysis is not required from the captured images. Rather, the object having the laser spot on it (i.e., the intended target) is tracked and the object continues to be tracked even after the laser spot has been removed. Thus, according to an embodiment, the only image recognition taking place by the guidance system is determining which object in the image has the laser spot, then tracking the position of that object in subsequent images.

In some embodiments, method 800 proceeds from operation 808 to operation 810 where a signal is transmitted indicating that the guidance method has changed. According to an embodiment, the guidance method changes from laser-based guidance to image-based guidance. The signal may be transmitted wirelessly using any of the protocols discussed earlier with reference to transceiver 410. The signal may be received by an operator of the vehicle that originally launched the projectile, or any other operator involved in the launch of the projectile. In some embodiments, no specific signal is transmitted, but the change from laser-based guidance to image-based guidance may be detected based on any output from the projectile's guidance system, or from the tracked or estimated position of the projectile.

FIG. 9 is a flowchart illustrating an example method 900 that may be performed by a vehicle that launches one or more projectiles towards enemy targets, or by an operator of the vehicle, in accordance with certain embodiments of the present disclosure. As can be seen, the example method includes a number of phases and sub-processes, the sequence of which may vary from one embodiment to another. However, when considered in the aggregate, these phases and sub-processes form a process for engaging with enemy targets in accordance with certain of the embodiments disclosed herein. The correlation of the various functions shown in FIG. 9 to the specific components illustrated in the other figures is not intended to imply any structural and/or use limitations. Rather, other embodiments may include, for example, varying degrees of integration wherein multiple functionalities are effectively performed by one system. For example, in an alternative embodiment a single module having decoupled sub-modules can be used to perform all of the functions of method 900. Thus, other embodiments may have fewer or more modules and/or sub-modules depending on the granularity of implementation. In still other embodiments, the methodology depicted can be implemented as a computer program product including one or more non-transitory machine readable mediums that when executed by one or more processors cause the methodology to be carried out. Numerous variations and alternative configurations will be apparent in light of this disclosure.

Method 900 may begin with operation 902 where a target is marked with a laser. The laser may be generated from a laser diode source present on the same vehicle having one or more projectiles to launch towards the target (such as on a helicopter). In some other embodiments, the laser is generated from a laser diode at a different location than where the one or more projectiles are launched from. Once the target is marked with the laser, the laser remains fixed on the target until a signal is received indicating that the laser can be removed, according to an embodiment.

Method 900 continues with operation 904 where one or more projectiles are launched towards the target. The one or more projectiles may be missiles having a motorized section or rockets without a motorized section.

In some embodiments, method 900 continues with operation 906 where a signal is received from the projectile indicating that a guidance method of the projectile has changed. According to an embodiment, the signal indicates that the guidance method of the projectile changes from a laser-based guidance method to an image-based guidance method. The signal may be received wirelessly using any of the protocols discussed earlier with reference to transceiver 410. Any output from the guidance system may be used to determine if the guidance method has changed from a laser-based guidance method to an image-based guidance method. In some other embodiments, an operator receives an indicator that the guidance method has changed based on either a tracked or estimated position of the projectile, which does not require receiving a particular signal from the projectile.

Method 900 continues with operation 908 where the laser is removed from the target. An operator may manually remove the laser from the target after receiving a signal from operation 906. In another example, the operator may receive some audio or visual indicator, such as a tone or a light, to indicate that the guidance method of the projectile has changed. In some examples, the operator may train the laser onto another target after receiving the indication that the laser is no longer required for guiding the projectile towards the first target. Another projectile can also be launched towards the new target. In some other examples, the operator may take evasive action or retreat after removing the laser from the target. In some embodiments, the laser is automatically removed upon the determination that the guidance method has changed.

Some of the embodiments discussed herein may be implemented, for example, using a machine readable medium or article which may store an instruction or a set of instructions that, if executed by a machine, may cause the machine to perform a method and/or operations in accordance with the embodiments. Such a machine may include, for example, any suitable processing platform, computing platform, computing device, processing device, computing system, processing system, computer, process, or the like, and may be implemented using any suitable combination of hardware and/or software. The machine readable medium or article may include, for example, any suitable type of memory unit, memory device, memory article, memory medium, storage device, storage article, storage medium, and/or storage unit, such as memory, removable or non-removable media, erasable or non-erasable media, writeable or rewriteable media, digital or analog media, hard disk, floppy disk, compact disk read only memory (CD-ROM), compact disk recordable (CD-R) memory, compact disk rewriteable (CR-RW) memory, optical disk, magnetic media, magneto-optical media, removable memory cards or disks, various types of digital versatile disk (DVD), a tape, a cassette, or the like. The instructions may include any suitable type of code, such as source code, compiled code, interpreted code, executable code, static code, dynamic code, encrypted code, and the like, implemented using any suitable high level, low level, object oriented, visual, compiled, and/or interpreted programming language.

Unless specifically stated otherwise, it may be appreciated that terms such as “processing,” “computing,” “calculating,” “determining,” or the like refer to the action and/or process of a computer or computing system, or similar electronic computing device, that manipulates and/or transforms data represented as physical quantities (for example, electronic) within the registers and/or memory units of the computer system into other data similarly represented as physical quantities within the registers, memory units, or other such information storage transmission or displays of the computer system. The embodiments are not limited in this context.

Numerous specific details have been set forth herein to provide a thorough understanding of the embodiments. It will be understood by an ordinarily-skilled artisan, however, that the embodiments may be practiced without these specific details. In other instances, well known operations, components and circuits have not been described in detail so as not to obscure the embodiments. It can be appreciated that the specific structural and functional details disclosed herein may be representative and do not necessarily limit the scope of the embodiments. In addition, although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described herein. Rather, the specific features and acts described herein are disclosed as example forms of implementing the claims.

Further Example Embodiments

The following examples pertain to further embodiments, from which numerous permutations and configurations will be apparent.

Example 1 is a guidance system for deployment on-board a projectile. The guidance system includes a laser-seeking detector, an imaging device, and a control module. The laser-seeking detector is designed to detect a position of the projectile with reference to a laser spot on a target. The imaging device is design to configured to capture one or more images in front of the projectile. The control module is design to control a flight direction of the projectile based on input received from the laser-seeking detector in a first mode, control the flight direction of the projectile based on input received from the imaging device in a second mode, and switch between the first mode and the second mode while the projectile is in flight towards the target.

Example 2 includes the subject matter of Example 1, wherein the one or more images captured by the imaging device include the target.

Example 3 includes the subject matter of Example 2, wherein the control module is configured to control the flight direction of the projectile towards the laser spot in the first mode, and the control module is configured to control the flight direction of the projectile towards the target in the one or more images in the second mode.

Example 4 includes the subject matter of any one of Examples 1-3, wherein the imaging device comprises an infrared camera.

Example 5 includes the subject matter of any one of Examples 1-4, wherein the flight direction of the projectile comprises one or more of an azimuth angle and an elevation of the projectile.

Example 6 includes the subject matter of any one of Examples 1-5, wherein the control module is configured to transition between the first mode to the second mode while the projectile is in flight towards the target.

Example 7 includes the subject matter of any one of Examples 1-6, wherein the control module is configured to switch from the first mode to the second mode when the projectile is a given distance from the target.

Example 8 includes the subject matter of any one of Examples 1-6, wherein the control module is configured to switch from the first mode to the second mode in response to determining that the target observed in the one or more images has the same angular location as indicated by the position detected by the laser-seeking detector.

Example 9 includes the subject matter of any one of Examples 1-8, wherein the control module is further configured to transmit a signal to an operator when switching from the first mode to the second mode.

Example 10 includes the subject matter of any one of Examples 1-9, wherein the projectile is a missile.

Example 11 includes the subject matter of any one of Examples 1-9, wherein the projectile is a rocket.

Example 12 is a projectile having a guidance system that includes a laser-seeking detector, an imaging device, and a control module. The laser-seeking detector is designed to detect a position of the projectile with reference to a laser spot on a target. The imaging device is design to configured to capture one or more images in front of the projectile. The control module is design to control a flight direction of the projectile based on input received from the laser-seeking detector in a first mode, control the flight direction of the projectile based on input received from the imaging device in a second mode, and switch between the first mode and the second mode while the projectile is in flight towards the target.

Example 13 includes the subject matter of Example 12, wherein the one or more images captured by the imaging device include the target.

Example 14 includes the subject matter of Example 13, wherein the control module is configured to control the flight direction of the projectile towards the laser spot in the first mode, and the control module is configured to control the flight direction of the projectile towards the target in the one or more images in the second mode.

Example 15 includes the subject matter of any one of Examples 12-14, further comprising a warhead.

Example 16 includes the subject matter of any one of Examples 12-15, wherein the flight direction of the projectile comprises one or more of an azimuth angle and an elevation of the projectile.

Example 17 includes the subject matter of any one of Examples 12-16, wherein the control module is configured to switch between the first mode to the second mode while the projectile is in flight towards the target.

Example 18 includes the subject matter of any one of Examples 12-17, wherein the control module is configured to switch from the first mode to the second mode in response to determining that the projectile is a given distance from the target.

Example 19 includes the subject matter of any one of Examples 12-17, wherein the control module is configured to switch from the first mode to the second mode in response to determining that the target observed in the one or more images has the same angular location as indicated by the position detected by the laser-seeking detector.

Example 20 includes the subject matter of any one of Examples 12-19, wherein the control module is further configured to transmit a signal to an operator when switching from the first mode to the second mode.

Example 21 includes the subject matter of any one of Examples 12-20, wherein the projectile is a missile.

Example 22 includes the subject matter of any one of Examples 12-20, wherein the projectile is a rocket.

Example 23 is a method of guiding a projectile to a target. The method includes receiving a position of a laser spot on a target; guiding the projectile towards the laser spot; receiving one or more first images in front of the projectile, the one or more first images comprising the target and the laser spot on the target; and in response to determining that a distance between the projectile and the target is less than a given threshold, guiding the projectile towards the target based on one or more second received images, wherein the one or more second images do not include the laser spot.

Example 24 includes the subject matter of Example 23, wherein receiving one or more images comprises receiving one or more images from an infrared camera.

Example 25 includes the subject matter of Example 23 or 24, wherein guiding the projectile comprises adjusting at least one of an azimuth and an elevation of the projectile.

Example 26 includes the subject matter of any one of Examples 23-25, further comprising transmitting a signal to an operator in response to determining that the distance between the projectile and the target is less than the given threshold.

Example 27 includes the subject matter of any one of Examples 23-26, wherein the projectile is a missile.

Example 28 includes the subject matter of any one of Examples 23-26, wherein the projectile is a rocket. 

What is claimed is:
 1. A guidance system for deployment on-board a projectile, the guidance system comprising: a laser-seeking detector configured to detect a position of the projectile with reference to a laser spot on a target; an imaging device configured to capture one or more images in front of the projectile; and a control module configured to control a flight direction of the projectile based on input received from the laser-seeking detector in a first mode, control the flight direction of the projectile based on input received from the imaging device in a second mode, and switch between the first mode and the second mode while the projectile is in flight towards the target.
 2. The guidance system of claim 1, wherein the one or more images captured by the imaging device include the target.
 3. The guidance system of claim 2, wherein the control module is configured to control the flight direction of the projectile towards the laser spot in the first mode, and the control module is configured to control the flight direction of the projectile towards the target in the one or more images in the second mode.
 4. The guidance system of claim 1, wherein the imaging device comprises an infrared camera.
 5. The guidance system of claim 1, wherein the flight direction of the projectile comprises one or more of an azimuth angle and an elevation of the projectile.
 6. The guidance system of claim 1, wherein the control module is configured to transition between the first mode to the second mode while the projectile is in flight towards the target.
 7. The guidance system of claim 1, wherein the control module is configured to switch from the first mode to the second mode when the projectile is a given distance from the target.
 8. The guidance system of claim 1, wherein the control module is further configured to transmit a signal to an operator when switching from the first mode to the second mode.
 9. A projectile, comprising: a guidance system, comprising a laser-seeking detector configured to detect a position of the projectile with reference to a laser spot on a target, an imaging device configured to capture one or more images in front of the projectile, and a control module configured to control a flight direction of the projectile based on input received from the laser-seeking detector in a first mode, control the flight direction of the projectile based on input received from the imaging device in a second mode, and switch between the first mode and the second mode while the projectile is in flight towards the target.
 10. The projectile of claim 9, wherein the one or more images captured by the imaging device include the target.
 11. The projectile of claim 10, wherein the control module is configured to control the flight direction of the projectile towards the laser spot in the first mode, and the control module is configured to control the flight direction of the projectile towards the target in the one or more images in the second mode.
 12. The projectile of claim 9, further comprising a warhead.
 13. The projectile of claim 9, wherein the flight direction of the projectile comprises one or more of an azimuth angle and an elevation of the projectile.
 14. The projectile of claim 9, wherein the control module is configured to switch between the first mode to the second mode while the projectile is in flight towards the target.
 15. The projectile of claim 9, wherein the control module is configured to switch from the first mode to the second mode when the projectile is a given distance from the target.
 16. The projectile of claim 9, wherein the control module is further configured to transmit a signal to an operator when switching from the first mode to the second mode.
 17. A method of guiding a projectile to a target, the method comprising: receiving a position of a laser spot on a target; guiding the projectile towards the laser spot; receiving one or more first images in front of the projectile, the one or more first images comprising the target and the laser spot on the target; and in response to determining that a distance between the projectile and the target is less than a given threshold, guiding the projectile towards the target based on one or more second received images, wherein the one or more second received images do not include the laser spot.
 18. The method of claim 17, wherein receiving one or more first images comprises receiving one or more first images from an infrared camera.
 19. The method of claim 17, wherein guiding the projectile comprises adjusting at least one of an azimuth and an elevation of the projectile.
 20. The method of claim 17, further comprising transmitting a signal to an operator in response to determining that the distance between the projectile and the target is less than the given threshold. 